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如何从 MapDB 中批量读取记录,而不是一次全部读取?

我有一个通过 MapDB 保存在磁盘上的 1,000 条记录的列表。

private fun storeRecordsInFile(records : List<Record>): String {
    val fileName = "/some/location/temp_file.db"
    val db = DBMaker.fileDB(fileName).fileMmapEnable().closeOnJvmShutdown().make()
    val diskBasedRecordsList = db.indexTreeList("recordsList").create()
    records.forEach { diskBasedRecordsList.add(it) }

    db.commit()
    db.close()

    return fileName
}

我能够一次阅读所有这些记录。

private fun readRecordsFromFile(fileName: String): List<Record> {
    val db = DBMaker.fileDB(fileName).fileMmapEnable().make()
    val diskBasedRecordsList = db.indexTreeList("recordsList").open()

    //read from disk based list
    val recordsList = mutableListOf<Record>()
    val size = diskBasedRecordsList.size
    for(i in 0 until size-1){
        recordsList.add(diskBasedRecordsList[i] as Record)
    }

    db.close()
    return recordsList
}

但是,我想在内存中一次仅读取 100 个块/批次(即不一次获取内存中的全部 1000 条记录)?

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